Dunnage air bags are widely used when transporting freight and cargo in containers, trailers, and train cars. Such bags are typically formed with a disposable construction and include conventional valve stem couplings adapted for connection to a conventional compressed air source supply hose. In use, the dunnage air bags are positioned around and adjacent to cargo and freight items, typically between individual freight items and between freight items and the walls of the corresponding container, train car, or trailer. The dunnage air bags are then inflated to cushion and protect the freight items from damage during transportation. After use or if a need to reposition arises, the dunnage air bags are typically pierced or ripped for purposes of rapid deflation, rendering them subsequently unusable. The used dunnage bags are then disposed as waste materials. In addition to time consuming and tedious inflation and deflation, wasteful one time use and subsequent disposable, conventional dunnage air bags require individual inflation and deflation. Accordingly, there is a need for and considerable interest in a dunnage air bag inflation and deflation device which allows reuse, repositioning, rapid inflation and deflation, and selective individual inflation and deflation of a plurality of dunnage bags through a manifold system.